A. Constitution
B. Elect Legislators that pass Laws on just any old thing that crosses their itty-bitty minds.
c. Pull it out of a hat.
tpaine, myself, and the Founders favored option #1. Whether you realize it or not, you are advocating option #2.
There are an indefinite number of things a State might need to do. You can't list them all in a State's Constitution. A certain amount of discretion is delegated by the People to the Legislators, by the Constitution.
We don't get protected by a Constitution because it lists every single thing that a state shall not do, we get protected because it lists the fundamental things that a state shall not do, and because it divides the government into branches that check and balance each other.
For example, SC's Constitution says that:
"Sec. 10. The right of the people to be secure in their persons, houses, papers, and effects against unreasonable searches and seizures and unreasonable invasions of privacy shall not be violated, and no warrants shall issue but upon probable cause, supported by oath or affirmation, and particularly describing the place to be searched, the person or thing to be seized, and the information to be obtained."
This provides protection from any number of things that the Legislature MAY do - such as outlaw prostitution. They can outlaw prostitution, but they can't peep into your windows at night to see if you're trading money for sex. This is the protection that you and tpaine are depending on. But SC does have the power to outlaw prostitution.